Hard drive jumpers?

Question

Can some one tell me what to put jumpers on if i already have 2 hdds in one as master and one as slave and this HDD shows on it a pic with 4 pins one pic having jumper on the 2 on the right which says "Limit to 1.5 Gb/s operation" and the other without any jumper says "3 Gb/s operation" and it came with the jumper on the right? any help would be great thanks.